def tennis_schedule(n):
    if n % 2 == 1:
        n += 1
        
    schedule = []
    
    players = list(range(1, n+1))
    
    for i in range(1, n):
        mid = n // 2
        first_half = players[:mid]
        second_half = players[mid:]
        second_half.reverse()
        
        round = []
        
        for j in range(mid):
            round.append((first_half[j], second_half[j]))
        
        schedule.append(round)
        
        players.insert(1, players.pop())
        
    return schedule

def print_schedule(schedule):
    for day, matches in enumerate(schedule, 1):
        print(f"Day {day}:")
        for match in matches:
            print(f"Player {match[0]} vs Player {match[1]}")

# 测试
n = 5
schedule = tennis_schedule(n)
print_schedule(schedule)
